NASA Struggles to Find Way Forward for Mars Sample Return

For the past three years, NASA's Perseverance rover has been exploring Jezero Crater on Mars in unprecedented fashion. For the first time in history, a robotic emissary has been collecting rock and atmospheric samples from another planet that are destined for analysis back on Earth, where scientists will be able to employ techniques that simply aren't available in situ.

The question is, how will we get the samples from there to here?

NASA and the European Space Agency (ESA) have been pursuing a plan to return the samples since before Perseverance launched, named (for now) the Mars Sample Return mission. And the plan was...complicated. First, NASA would launch a Sample Retrieval Lander in 2028. Once it landed on Mars, Perseverance would deliver samples to the lander. (Helicopters or rovers might accompany the lander to aid in retrieval.) The lander would then launch off of Mars via a Mars Ascent Vehicle. The MAV would go to orbit around the Red Planet, where it would meet another vehicle that would then carry the mission back to Earth. (Find a full, illustrated outline of the mission concept here.)

When Perseverance launched, the samples were expected to be returned by 2031 at earliest. The astronomy community's decadal survey affirmed the mission at a budget of $5-7 billion. The Mars Sample Return passed its first independent review board evaluation with flying colors. However, a second independent review didn't go so well, finding that the mission couldn't be accomplished within the current budget. Either the mission would need to be stretched out to a return date of 2040, or the budget needed to grow significantly, to $8-11 billion.

Today, NASA Administrator Bill Nelson acknowledged the second independent review's report, calling the needed budget "too expensive" and the 2040 timeline "unacceptably too long." The needed funding for Mars Sample Return, as it is now, would cannibalize other, existing missions, he said, including the Dragonfly mission to Saturn's moon Titan, the DAVINCI and VERITAS missions to Venus, and the Near-Earth Object Surveyor.

Instead, Nelson and Associate Administrator Nicky Fox are calling for alternative mission architectures. "I have asked our folks to reach out with a request for information to industry, to the Jet Propulsion Laboratory, and to all NASA centers," Nelson said at the April 15th press conference, "and to report back this fall an alternate plan that would get [the samples] back quicker and cheaper."

What those alternatives would look like is, at this point, anyone's guess. Fox did, however, emphasize that the agency is looking for tried-and-true technologies. "Thereby, we can lower the risk and the cost and also the time for development," she added. "Anything requiring huge leaps in technology usually, from experience, takes a lot of time."

"The solicitation should go out tomorrow," Fox added, outlining a two-step process. "The due date for proposals would be May 17th. . . . Once we've got the award to the various partners, we would give them 90 days to respond with their studies." After the studies are received, NASA will need to evaluate them; Fox did not give an estimated time frame for any decisions.

"Remember, we were put in this situation because of the cutbacks by Congress . . . that's what we are having to respond to," Nelson said. "We made the choice that, of those that were arguing that this program should be zeroed out, that this was too important to our country, that returning the samples from Mars remains an important operation."